Preparation and Properties of Al_2O_3/TiO_2 Nanometer Antimicrobic

Al_2O_3/TiO_2 nanometer antimicrobic with n(Al_2O_3)/n(TiO_2)=0.2 was prepared by co-precipitation method using TiCl_4 and Al_2(SO_4)_3 as raw materials.The effect of composite agent Al_2O_3 on antimicrobial properties of nanometer TiO_2 was studied using DSC-TG,XRD and UVvis.The results show that nanometer TiO_2 compounded by Al_2O_3 calcined at 900 ℃ has entirely the anatase structure,and that calcined at 950～1050 ℃ has well mixed crystalline structure.TiO_2 nanocomposite calcined at 950 ℃ is well mixed crystalline structure in which the mass fraction of anatase is about 77%,the average particle size is about 20 nm,and the red shift of absorption band is remarkable,i.e.optical absorption edge extended from 380 nm of pure TiO_2(calcined at 700 ℃) to 430 nm,and the antibacterial circle reaches about 15 mm under fluorescent lamp against colibacillus and staphylococcus.